The top corporate tax rate in the United States is too high, and relative to the rest of the world, it is getting higher:

High U.S. corporate tax rates make it difficult for businesses to compete internationally. While other countries are reducing corporate tax rates, the U.S. has maintained a rate of 35 percent, the highest of any nation in the Organisation for Economic Co-operation and Development (OECD).

This harms individual states, too. Low tax Texas, for example, could compete much better against European and Asian economies, if we didn't have these high national corporate rates dragging us down.